The full article in the BMJ is here. It simply confirms the same increased incidence in the UK as has been found elsewhere in countries that used Pandemrix, although initially it was said Scandinavians had very high rates of autoimmune disorders and were at higher risk than others.
Given the up to 10 year interval between disease onset and diagnosis, we won't know for awhile how wide the age spread is that was affected (it might have affected all ages).
The take home message, which I have recited many times before, is that you will not know until long after a massive vaccine campaign has been completed whether there are horrific side effects. You won't know unless you improve surveillance, reporting, and make rapid case ascertainment your priority.
You also are unlikely to know about side effects unless they are really severe (as this one is) and if they occur at many times the expected rate (narcolepsy occurring in teens 13 times more than expected). To me, that is absolutely not acceptable.